| 摘要 |
PURPOSE:To perform accurate focus detection regardless of whether an image is out of focus greatly or slightly by employing a lateral shifting method for the focusing detection when the evaluated value by an out-of-focus image method is less than a specific value, and employing both of the out-of-focus image method and lateral shifting method when said evaluated value is greater than the specific value. CONSTITUTION:When an out-of-focus image is detected, a photodetecting element array is arranged on a plane equivalent to planes 101 and 102 distant from an expected focal plane 100 forward and backward. A photodetecting element array for detecting a lateral shift is arranged on a plane equivalent to the expected focal plane 100. An out-of-focus image detecting circuit 30 holds the photodetection outputs of the element arrays 31 and 32 by circuits 33 and 34 to find and store the maximum values FB1 and FB2 of output differences between adjacent elements by processing circuits 39 and 40 through an A/D converter 35, and outputs a difference S to obtain a front-focus, in- focus, or rear-focus signal through a comparator 70. In a lateral shift detecting circuit 50 the evaluated value is obtained from the output of the element array 51 and inputted to a comparator 80. The FB1 and FB2 are compared with the threshold value and at a gate there is selected both systems. |
